People Eat Healthier When Given More Options

Some studies have shown that calorie labels at fast-food restaurants have little effect on consumption, so scientists at Duke University tried something different: They offered customers at a local Chinese restaurant the option of a smaller portion.

In a first experiment, with 283 people, only 1 percent asked for a smaller portion of a starchy side dish when none was explicitly offered. But when servers told customers they could choose a portion containing 200 fewer calories, 33 percent accepted.

In a second test, with 992 participants, the researchers labeled the dishes on the menu with the number of calories. This did not increase the number of diners who accepted smaller portions.

In a final trial, the researchers tracked the orders and weighed the leftovers of 263 customers and found that those who chose smaller side dishes did not compensate by ordering higher-calorie entrées. Those who opted for larger side dishes did not leave significantly more food on their plates than the downsizers.

The senior author of the study, Dan Ariely, a professor of psychology at Duke, compared this dietary strategy to Odysseus having sailors tie him to the mast so he could resist the call of the Sirens.

“People are willing to perform an act that limits their freedom but basically improves their long-term well-being,” he said. “We should think about more places where we could offer these choices.”